[PATCH] D11815: Pass subtarget feature "force-align-stack"

[Akira Hatanaka via cfe-commits]

ahatanak added a comment.

In http://reviews.llvm.org/D11815#236368, @vkalintiris wrote:

> In http://reviews.llvm.org/D11815#235394, @ahatanak wrote:
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> >
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> For example, on a Mips target, where the O32 ABI requires either way an 8-byte alignment, we would generate redundant code for realigning the stack to a 4-byte alignment if a function contains objects with maximum alignment of 4-bytes (see attached files to get an idea).


I wonder if there is a target or a use case that requires or prefers realigning the stack to an alignment that is smaller than the default stack alignment.  If there is no such target or use case, I think we can just using the existing attribute StackAlignment (with value 0) rather than adding a new function attribute "stackrealign", which will ensure the stack is at least aligned to the default value and force realigning the stack.


http://reviews.llvm.org/D11815